The present invention relates to a neutral electrode for HF surgery and to a conductive gel for use with such a neutral electrode.
When employing neutral electrodes care should always be taken to keep the contact resistance between the skin and the electrode apposed thereto from becoming too high, so as to prevent excessive warming of the human tissue by a flowing HF treatment current. High contact resistances occur primarily in patients with extremely dry skin, in adipose patients because of the high fat content of the tissue, or in some cases of very hairy skin, when the dense hairs prevent complete contact between electrode and skin. The hairs can easily be removed by shaving. To deal with the problems of dry skin or adipose tissue, however, is distinctly more difficult. In order to prevent severe warming or even burning of the human tissue, therefore, the customary neutral electrodes have large surface areas, which counteract high current densities. Often several electrodes are employed in order to enlarge the effective area and thus reduce the current density.
The reduction of contact resistance, in particular when there are problematic skin and/or tissue conditions, can often be accomplished only by the use of multiple electrodes or by making an electrode larger. However, this increases the costs and furthermore makes it more difficult to manipulate the electrodes.